Evening star. [volume] (Washington, D.C.) 1854-1972, 1887-06-11
Americas Inland Seas.
INTERESTING FACTS ABOUT THE GREAT LAKES AND
THEIR OUTLETS.

Amer1cA'0 Inland Seas
INTERESTING FACTS ABOUT THE GREAT LAKES ANn
THEIR OUTLETS.
It has long been known that the Great Lakes
are subject to remarkable and seemingly capric-
ious changes OF level. These changes are roughly
registered In the varying volume Of the st. Law.
renee, that remarkable river itself the outlet Of
these great lakes, and in q sense q continuation
and part OF the lakes themselves In some years
the St. Lawrence, which drains q watershed Of
over 5OO, 600 square miles, is much fuller all sum-
mer than In other years 1t leaves Lake Erie, al.
cataract OF Niagara it descends With its enormous
mass OF nearly 100000 cubic feet OF water In every
second OF time.
This almost 1ncomprehensible mass OF water
tne drainage or overflow OF all the great lakes va
res In volume with the level OF the lakes Of which
se%e
tidal movements or changes OF level in Lake
Michigan. This, the second in size and depth q
water on the globe-ls subject 10 great ductua-
lions, being several feet lower In some years
!apa IN a, Others. Lake Michigan is DEEP
Practlcaliy as deep as Lake Superior. II
mas 6een 1t seems, for nearly thirty years, the
81 Of o the to
Kee. me water which at that point (as the
cling1ng memory of plunge into it at the close OF
as it is at Mackinaw~is usually foot or two
higher In summer than 1t is in winter; but
IN some s years the variation is equal to three
body of water, an enormous difference. Lake
superior alone Is almost large the great State
OF ONO, while Lake Michigan, the direct receiver
OF lts overflow, about as large as Massachusetts,
Vermont, and New Hampshire put together. A
change OF three or four feet in the level OF these
great lakes implies difference in the amount OF
water too great to be fully understood and appre-
ciated The other lakes necessarily participate IN
Inese fluctuations; but these appear to be most
marked in Lake Michigan.
Thelr cause is not yet wholly understood. Var
IouS CneOrleS nave been advanced TO account Tor
tnem-even to the absurd extent OF connecting
simpler explanation seems more probable 1t
would seem as II the higher level in Lake M1chi-
gan In summer and autumn may be caused by the
spring and summer rains and late melting SHOWS
Lake Superior with its rushing streams and
coplous rivers. In that immense lake rise
OF single foot Is equivalent to q much
greater rise in the lesser lakes OF the great system
Ihat the fluctuations should be Irregular, show
Ing Tar greater level In some years tnan1n Others
might we'll be due TO the varying quantities OF May
ana June rain In different years and to the greater
quantities OF snow remaining in those hyper.
Dorean lat1tudes to be duly transformed, in May
ana June Into water. or course he1ntiux received
by the larger lake would be lar less in winter
and hence the lakes would be the lowest in
winter, and highest in summer and autumn.
Whatever the cause may be, the occurrence
itself OF these large fluctuations in the Levels Of
sucn vast bodies OF water is one OF the striking
facts In the worlds greatest system and
Wen worthy OF philosophical examination. That
lake ana river System-or, perhaps 1t might be
called all one great river, 1000 miles longSis the
most interesting one on Inc globe. Its greatest
expanSion-the vast Lake Superior-iS at level
OF over 600 feet above the sea; u Ake whose area
Is 81 900 square miles in extent, and whose depth
Is 1000 feet. The river flows Oh its Iordiy course
through the rocks OF the Laulent1an system, the
Oldest on the globe, and it receives its af1uent
the dark wild waters OF the Saguelay.